The picture shown is beautiful. If you do something like this, be sure to use well dried poplar as your base wood. Anything else is likely to give you trouble due to proximity to heat. You will want to make some part of it removable for cleaning out the inevitable dust bunnies that clog circulation. And all surfaces, front, back, top, bottom, ends get the same finish treatment (or else!)
I used to build entire cabinets over baseboard heaters. The trick was to use a false back and false bottom with enough vents to provide the original circulation. The cabinet itself had to be vented at least on top to let accumulated heat escape. I usually concealed the vents in the toe space and behind shutters or other distraction.
Good luck!
DanK

 

Could you use MDF for the raised panels? Would that be a less expensive option than poplar?

 

cool design Pat, great job.

 

Thanks for the input. I think MDF is what I am going to use. I just finshed making the baseboards for the other walls that don't have heaters on them and MDF is what I used. It worked well and was much cheaper than buying pre made baseboards from the hardware store plus I was able to get the exact look I wanted.

 

Yes, MDF will work pretty well. The product has improved greatly in recent years but my early experiences with it left much to be desired back then.
Good Luck.
DanK

 

Using an exterior grade MDF would be even better. It is more dense, and when sealed with a good primer (I use Seal Coat) will paint very well. This stuff is almost bullet proof.
Bill